Almegård B, Andersson S E
Department of Physiology and Medical Biophysics, University of Uppsala, Sweden.
Exp Eye Res. 1990 Dec;51(6):685-9. doi: 10.1016/0014-4835(90)90053-w.
A study in cats has shown that intracameral injection of calcitonin gene-related peptide (CGRP) increases the outflow facility by four- to fivefold concomitant with a decrease in intra-ocular pressure (IOP). Since there are great differences in the anatomy of the aqueous outflow routes between cats and primates, we have examined the effects of CGRP in the cynomolgus monkey. The possible influence of the sensory neuropeptides cholecystokinin (CCK), galanin and substance P on the outflow facility and IOP were also investigated. Determinations were performed using a two-level constant-pressure procedure. At 40-60 min after intracameral injection of 3 micrograms CGRP the outflow facility was increased from 0.68 +/- 0.11 to 1.03 +/- 0.15 microliters min-1 mmHg-1 in the CGRP-treated eyes, and from 0.71 +/- 0.12 to 0.79 +/- 0.10 microliter min-1 mmHg-1 in the control eyes. The mean difference in increase was 0.27 +/- 0.06 microliter min-1 mmHg-1 (P less than 0.01, n = 7). During the experiments there was a small rise in the IOP. CGRP at a dose of 3 micrograms caused a small rise in aqueous humor protein concentration. An attempt to release endogenous CGRP with capsaicin did not result in an increased outflow facility. Three micrograms each of CCK, galanin and substance P had no significant effect on either the outflow facility or the IOP. A miosis was observed in the experiments with CCK in agreement with previous findings. CCK seems thus to cause contraction of the pupillary sphincter but does not influence the ciliary muscle sufficiently to cause a facility effect in the monkey eye.(ABSTRACT TRUNCATED AT 250 WORDS)
一项针对猫的研究表明，前房内注射降钙素基因相关肽（CGRP）可使房水流出易度增加4至5倍，同时眼内压（IOP）降低。由于猫和灵长类动物的房水流出途径在解剖结构上存在很大差异，我们研究了CGRP对食蟹猴的影响。还研究了感觉神经肽胆囊收缩素（CCK）、甘丙肽和P物质对流出易度和眼内压的可能影响。使用两级恒压程序进行测定。在前房内注射3微克CGRP后40 - 60分钟，CGRP处理组眼睛的流出易度从0.68±0.11增加到1.03±0.15微升·分钟⁻¹·毫米汞柱⁻¹，对照组眼睛从0.71±0.12增加到0.79±0.10微升·分钟⁻¹·毫米汞柱⁻¹。增加的平均差异为0.27±0.06微升·分钟⁻¹·毫米汞柱⁻¹（P＜0.01，n = 7）。实验过程中眼内压有小幅升高。3微克剂量的CGRP使房水蛋白浓度有小幅升高。用辣椒素释放内源性CGRP并未导致流出易度增加。各3微克的CCK、甘丙肽和P物质对流出易度或眼内压均无显著影响。在CCK实验中观察到瞳孔缩小，与先前的研究结果一致。因此，CCK似乎会导致瞳孔括约肌收缩，但对睫状肌的影响不足以在猴眼中产生流出易度效应。（摘要截短至250字）
